| Attert | |
| Map: | Attert River Map.png |
| Mouth Coordinates: | 49.8149°N 6.0961°W |
| Subdivision Type1: | Country |
| Length: | 38km (24miles) |
| Source1 Elevation: | 406m (1,332feet) |
| Basin Size: | 299km2 |
The Attert (pronounced as /fr/, pronounced as /de/;) is a river flowing through Belgium and Luxembourg, left tributary of the Alzette. Its length is 38km (24miles), of which 32km (20miles) are in Luxembourg and 6km (04miles) in Belgium. Its source is in Nobressart, north-west of Arlon, in the Belgian province Luxembourg. It flows into the river Alzette at Colmar-Berg. It flows through the village of Attert in Belgium, and the towns of Redange, Everlange, Useldange, Boevange-sur-Attert, and Bissen in Luxembourg.